Recent data suggest that the prevalence of obesity among children and youth stayed relatively constant over this period. Nevertheless, the social and economic costs of pediatric obesity increased, say Leonardo Trasande, an assistant professor of community and preventive medicine at Mount Sinai School of Medicine in New York City, and coauthors.

Hospitalizations of children and youth ages 2-19 with a primary or secondary diagnosis of obesity increased from 21,743 in 1999 to 42,429 in 2005. Over this period, obesity-related hospitalizations increased 8.8 percent per year among children ages 2-5, 10.4 percent per year among children ages 6-11, and 11.4 percent per year among adolescents ages 12-19. Total costs for children and youth with obesity-related hospitalizations increased from $125.9 million in 2001 to $237.6 million in 2005, measured in 2005 dollars.

Trasande and his colleagues used data from the Nationwide Inpatient Sample, the largest all-payer database for U.S. hospitalizations. They found that among hospitalizations for which obesity was listed as a secondary diagnosis, affective disorders were the most frequent primary diagnoses, followed by pregnancy-associated conditions, asthma, and diabetes. Over the 1999-2005 period, the researchers found statistically significant increases in obesity-related hospitalizations for asthma, pregnancy-related conditions, diabetes, pneumonia, skin/subcutaneous tissue infections, appendicitis, certain mental conditions, and biliary tract disease.

The Costs To Medicaid Of Pediatric Obesity

According to Trasande and coauthors, Medicaid bears a large burden for hospitalizations with a secondary diagnosis of obesity, while private payers pay a greater portion of costs for hospitalizations with obesity as a primary diagnosis. Obesity-related hospitalizations cost Medicaid $118.1 million in 2005, up from $53.6 million in 2001 -- a 120 percent increase.

“Indeed, just as growth in the elderly population has contributed to increases in health care costs, increasing obesity among children appears to be driving increases in Medicaid spending,” Trasande and coauthors observe. “Given the increasing burden of obesity-associated hospitalizations, our findings suggest that additional federal support of prevention programs could reduce obesity treatment costs borne by federal and state governments.”

The Clinical Definition Of Obesity Versus A Diagnosis Of Obesity

According to an American Medical Association expert panel, a child is obese if his or her body mass index (BMI) -- a measure derived from the child’s height and weight -- is at or above the 95th percentile. Trasande and coauthors point out that in contrast to this definition, obesity as a diagnosis “is a product of clinical judgment and reimbursement by hospital payers and is subject to inaccuracy.”

Thus, the researchers note, their results must be interpreted with caution because they could represent in part an increased recognition of obesity rather than an increase in the rate at which obesity is contributing to other medical conditions. However, “even if increased recognition has contributed to these trends, our analysis suggests that obesity has a much more immediate impact on the health of children, especially adolescents, than previously understood,” write Trasande and coauthors Yinghua Liu and Michael Weitzman of the New York University School of Medicine and George Fryer of the University of Arkansas.

Indeed, the authors say, obesity appears to remain undercoded during hospitalizations. “If obesity prevalence among children with asthma is roughly equal to that for all American children, then one would expect about 20 percent of children hospitalized with asthma to be obese, yet we found less than 2 percent of asthma hospitalizations with obesity listed as a comorbidity,” Trasande and his colleagues point out.

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